The TowSmart X-Mount Ball Mount is a patented X-Mount design that channels away moisture to minimize seizing within the aperture of the receiver hitch. The X-Mount design also includes a lockrail system that allows you to torque the hitch ball with a single wrench. The lockrail functions as a built-in wrench preventing the hitch ball rotation during installation or removal from the X-Mount Ball Mount. Make sure to select the correct class for your towing application. Each X-Mount can be used in either the drop or rise position depending on your requirement when towing. It is important to know the total weight of the trailer (GTW) you are towing and the maximum towing capacity determined by the vehicle manufacturer.